Ozark is a city in Franklin County, Arkansas, United States, and (along with Charleston) one of the two county seats of Franklin County. It is part of the Fort Smith, Arkansas-Oklahoma Metropolitan Statistical Area. The population was 3,525 at the 2000 census, making Ozark the ninth largest municipality in the metro area. Ozark is the point at which the Arkansas River is farthest north in the state. The name "Aux Arc", later simplified to Ozark, was given to this bend of the river by the French explorers when they were mapping out this land.